In recent years, in a semiconductor manufacturing process, further improvement in fine processing technology has been required according to higher integration or higher performance of an element. In the semiconductor manufacturing process, an etching technology is the important one of fine processing technologies, and in recent years, among etching technologies, a plasma etching technology which has high efficiency and in which fine processing of a large area is possible has become mainstream.
The plasma etching technology is one type of dry etching technology. In the plasma etching technology, a mask pattern is formed on a solid material that is a workpiece by using a resist, the solid material is supported in a vacuum, a reactive gas is introduced into the vacuum in this state, a plasma state that is made by collision of electrons accelerated by applying a high-frequency electric field to the reactive gas with gas molecules is generated, and radicals (free radicals) and ions that are generated from the plasma react with the solid material, whereby the solid material is removed as a reaction product. Due to such a process, the plasma etching technology forms a fine pattern in the solid material.
In the past, in a semiconductor manufacturing device using plasma, such as a plasma etching device, an electrostatic chuck device has been used as a device to easily mount and fix a wafer onto a sample stage and maintain the wafer at a desired temperature.
Incidentally, in an existing plasma etching technology, if a wafer fixed to an electrostatic chuck device is irradiated with plasma, the surface temperature of the wafer rises. In order to suppress a rise in the surface temperature, the wafer is cooled from the underside by circulating a cooling medium such as water to a cooling plate section of the electrostatic chuck device. At this time, temperature distribution occurs in the plane of the wafer. For example, at a central portion of the wafer, the temperature becomes high, and at a marginal portion, the temperature becomes low. Further, due to a difference or the like of a structure or a system of the plasma etching device, a difference occurs in in-plane temperature distribution of the wafer.
Therefore, an electrostatic chuck device with a heater function has been proposed in which a heater member is mounted between an electrostatic chuck section and a cooling plate section (refer to PTL 1, for example). In the electrostatic chuck device with a heater function, since it is possible to locally make temperature distribution in a wafer, by setting temperature to match the in-plane temperature distribution of the wafer with a film deposition rate or a plasma etching rate, it is possible to efficiently perform local film formation or local plasma etching such as pattern formation on the wafer.
As a method of mounting a heater on the electrostatic chuck section, there is a method of incorporating a heater into an electrostatic chuck section made of ceramic; a method of applying a heater material to the back side of an adsorption surface of an electrostatic chuck section, that is, the rear surface of a ceramic plate-shaped body in a predetermined pattern by a screen printing method and heating and curing the heater material; a method of sticking metal foil or a sheet-shaped conductive material to the rear surface of the ceramic plate-shaped body, or the like. An electrostatic chuck device with a heater function is obtained by bonding and integrating the heater built-in electrostatic chuck section or an electrostatic chuck section with a heater mounted thereon and a cooling plate section that cools the electrostatic chuck section through an organic adhesive layer.